How to Use a Hall Effect Sensor with Arduino (Lesson #31)

Does your home have any pet doors or gates for dogs, cats, or other animals? Some automatic pet doors can be set up to allow only certain animals through. These doors can help you control which pets are able to go outside alone or which ones have access to specific food, litter boxes, or toys. But why buy such a door when you can make one? In this project you will build your own automatic pet door that works with a magnetic collar tag. Exactly how you use it is up to you! Read more

Stop for a minute and try to imagine your world without electrical power and electronic gadgets. No convenient appliances in the kitchen, no electric lights. No computers, MP3 players, television, or video games. Your life would be completely different, wouldn't it? Electricity and electronics are so central to modern life that, paradoxically, they're easy to overlook. … Read more